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Global asymptotic stability of cellular neural networks with multiple delays

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Progress in Natural science:Materials International 2006年第2期16卷 163-168页

作者： WANG Zhanshan and ZHANG Huaguang ( Key Laboratory of Process Industry Automation, Northeastern university, shenyang 110004, china Department of information engineering, shenyang Ligong university, shenyang 110168, china) [a]Key Laboratory of Process Industry Automation Northeastern University Shenyang China [b]Department of information engineering Shenyang Ligong University Shenyang China

Global asymptotic stability (GAS) is discussed for cellular neural networks (CNN) with multiple time delays. Several criteria are proposed to ascertain the uniqueness and global asymptotic stability of the equilibrium point for the CNN with delays. These criteria can eliminate the difference between the neuronal excitatory and inhibitory effects. Two examples are presented to demonstrate the effectiveness of the criteria.

关键词： cellular neural networks global asymptotic stability multiple time delays.

Multimedia Data Coding and its Development

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International Journal of Minerals,Metallurgy and Materials 2000年第3期14卷 229-232页

作者： Xingye Yu, Yang Yang (information engineering school, university of science and technology Beijing, Beijing 100083, china) information engineering school University of Science and Technology Beijing Beijing 100083 China

The requirements of data coding in multimedia applications are presented, the current technique of coding and relative standards is introduced, then the work that have been doing is presented, i.e. the wavelet-based coding method and the VE (Visual Entropy)-based coding method. The experiment results prove that these methods have gained a better perceptual quality of a reconstructed image and a lower bit rate. Their performance evaluations are better than JPEG (Joint Photographic Experts Group) coding. Finally, the future topics of study are put forward.

关键词： multimedia data coding MPEG (Moving Picture Experts Group) VE (Visual Entropy)

A WT-STFT combining Algorithm

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International Journal of Minerals,Metallurgy and Materials 2000年第4期14卷 315-317页

作者： Xisheng Li, Shaochun Wang (information engineering school, university of science and technology Beijing, Beijing 100083, china) information engineering school University of Science and Technology Beijing Beijing 100083 China

A fast wavelet packet (WP) algorithm is presented, in which the wavelet transform (WT) and the short-time Fourier transform (STFT) are combined. As WT produces multiresolution of frequency and time, and STFT has a fas... 详细信息

关键词： signal processing, wavelet transform short-time Fourier transform Informatid

Improvement of Boxcar Integrator and Its Application to Low Resistance Measurement of Inductive Load Coil

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International Journal of Minerals,Metallurgy and Materials 1998年第3期12卷 180-184页

作者： Xisheng Li Shaochun Wang(information engineering school, university of science and technology Beijing, Beijing 100083, china) information engineering school University of Science and Technology Beijing Beijing 100083 China

A boxcar integrator is described which is suitable for the low-repetition-rate signal processing. This boxcar integrator, named fixed-interval mode boxcar integrator, is able to reject harmonics other than the first harmonic component. It can also decrease the effective time constant In many situations, the antialiasing filter with narrow bandwidth will cause distortion of the input signal. The fixed-interval mode boxcar integrator with suitable gate width can achieve relative high performance without signal distortion because the bandwidth of its antialiasing filter can be wider than that in the fixed-Point boxcar integrator. ms boxcar integrator is used as majn part of signalprocessing circult in the low resisance measurement of inductive load coil. The results of experiments show that the fixed-interval boxcar integrator is suitable for low-repetition-rate use.

关键词： signal processing resistance measurement boxcar integrator

Optimization of Fractal Iterated Function System(IFS) with Probability and Fractal Image Generation

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Journal of university of science and technology Beijing 2001年第2期8卷 152-156页

作者： Berthe Kya, Yang Yang (information engineering school, university of science and technology Beijing, Beijing 100083, china) Univ Sci & Technol Beijing Informat Engn Sch Beijing 100083 Peoples R China

There are several methods for rendering fractal images based on IFS (Iterated Function System) in computer graphic; but one concern of the computer graphic community has been the efficiency rendering algorithms. The invariant measures arising from IFSP (Iterate Function System with Probability) using the probabilistic algorithm are also known as chaos games. The role of these probabilities to generate the image of the attractor has been investigated using a multi-fractal analysis. The conventional choice of probability associated with each set /S/ to generate the attractor in least time possible is introduced, then a new method based on the self similarity and multi-fractal analysis is presented. The efficiency of the new method has been proved over the conventional method.

关键词： optimization of fractal IFS compression IFSP multi-fractal analysis

Materials Design of Microstructure in Grain Boundary and Second Phase Particles

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Journal of Materials science & technology 2003年第2期19卷 97-101页

作者： Yaping ZONG and Liang ZUODepartment of Materials science and engineering, Northeastern university, shenyang 110004, china Dept. of Mat. Sci. and Eng. Northeastern Univ. Shenyang 110004 China

A concept of microstructure design for materials or materials microstructure engineering is proposed. The argument was suggested based on literature review and. some our new research work on second phase strengthening mechanisms and mechanical property modeling of a particulate reinforced metal matrix composite. Due to development of computer technology, it is possible now for us to establish the relationship between microstructures and properties systematically and quantitatively by analytical and numerical modeling in the research scope of computerization materials. Discussions and examples on intellectual optimization of microstructure are presented on two aspects: grain boundary engineering and optimal geometry of particulate reinforcements in two-phase materials.

关键词： Microstructure design Particulate reinforcement Grain boundary engineering Strengthening mechanism Eshelby approach Numerical modelling

Numerical optimization method for HJI equations derived from robust receding horizon control schemes and controller design

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science china(information sciences) 2012年第1期55卷 214-227页

作者： SONG ChongHui,BIAN ChunYuan,ZHANG Xie&SHI ChengLong school of information science and engineering,Northeastern university,shenyang 110004,china 1. school of information science and engineering Northeastern University Shenyang 110004 China

This paper addresses how to numerically solve the Hamilton-Jacobin-Isaac(HJI)equations derived from the robust receding horizon control *** developed numerical method,the finite dierence scheme with sigmoidal transformation,is a stable and convergent algorithm for HJI equations.A boundary value iteration procedure is developed to increase the calculation accuracy with less time *** obtained value function can be applied to the robust receding horizon controller design of some kind of uncertain nonlinear *** the controller design,the finite time horizon is extended into the infinite time horizon and the controller can be implemented in real *** can avoid the on-line repeated optimization and the dependence on the feasibility of the initial state which are encountered in the traditional robust receding horizon control schemes.

关键词： dynamic programming uncertain nonlinear systems numerical method robust receding horizon control dierential game

Controlled Rolling and Cooling Process for Low Carbon Cold Forging Steel

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Journal of Wuhan university of technology(Materials science) 2010年第1期25卷 89-93页

作者：李壮 school of Materials science and engineering Shenyang Institute of Aeronautical Engineering

Effect of controlled rolling and cooling process on the mechanical properties of low carbon cold forging steel was investigated for different processing parameters of a laboratory hot rolling mill. The results show that the specimens with fast cooling after hot rolling exhibit very good mechanical properties, and the improvement of the mechanical properties can be attributed mainly to the ferrite-grain refinement. The mechanical properties increase with decreasing final cooling temperature within the range from 670 ℃ to 570 ℃ due to the finer interlamellar spacing of pearlite colony. The specimen with fast cooling after low temperature rolling shows the highest values of the mechanical properties. The effect of the ferrite grain size on the mechanical properties was greater than that of pearlite morphology in the present study. The mechanical properties of specimens by controlled rolling and cooling process without thermal treatment were greatly superior to that of the same specimens by the conventional rolling, and their tensile strength reached 490 MPa grade even in the case of low temperature rolling without controlled rolling. It might be expected to realize the substitution medium-carbon by low-carbon for 490 MPa grade cold forging steel with controlled rolling and cooling process.

关键词： controlled rolling and cooling process low carbon cold forging steel fast cooling low temperature rolling the ferrite-grain refineme

Optimum Design of Movable Screen Jig Cycle

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International Journal of Minerals,Metallurgy and Materials 1999年第4期13卷 246-249页

作者： Chunbao Sun Yubo Sun(1 Resources engineering school, university of science and technology Beijing, Beijing 100083. china2 Department of Mineral engineering, Northeastern university. shenyang 10006. china) Resources engineering school University of Science and Technology Beijing Beijing 100083 China Department of Mineral engineering Northeastern University Shenyang 110006 China

The basic method for designing and calculating reasonable jig cycle of movable screen jig was presented. The reasonabilityand reliability of designed jig cycle were verified by' means of the test on artificial mixed materials. An iron ore (12-100 mm) was treatedin tile TJD-75 model movable screen jig with the jig cycle. The good results were achieved. This would provide a reliable basis for designof commercial movable-screen jig.

关键词： movable-screen jig jig cycle optimum design